Quality control devices for containers are also known based on optical systems that allow the optical reconstruction of the containers by means of in-sequence capturing devices of successive angular sectors of the container placed in rotation or rota-revolution, where such plurality of views and the number of images captured are handled through handling means during the movement of the container.
Quality control devices are also known that operate independently on a production line.
Such machines are normally equipped with fixed TV cameras in front of which the container transits in rotation and a lighting device with a pre-established angle of incidence adapted to maximize the quantity of reflected light and therefore the possibility of resolution of the plurality of images handled for the optical reconstruction of the entire side surface of the container.
Such machines are however characterized by limited productivity and the imprecision of the optical reconstruction of the container in the case of side walls of the container—or portions of the side walls—that have concave and/or convex surfaces on which the angle of incidence of the light of the lighting device and therefore the angle of reflection vary, generating shaded zones of lower optical resolution and therefore imprecision of the reading of the image and optical reconstruction of the container.
In particular, such imprecisions become unacceptable for the quality control of closures of containers through mechanical crushing to deform the closing element, generally metal or another ductile material, onto a container contrast element, generally cylindrical.
Such operation, known in technical jargon as “crimping”, typically used for sealed containers in the pharmaceutical industry but not only, generates surfaces at high mutual angles, even orthogonal, and undercuts in the specific closing area where the profoundly different angles of reflection of the light generated by the lighting device placed at a fixed angle with respect to the container prevent the correct, reliable and complete optical reconstruction of the closing element subjected to quality control.